A grieving father has sued Google, Twitter and Facebook, alleging the web giants enabled the Paris terrorist attacks that killed his daughter.

Nohemi Gonzalez, 23, was a student spending a semester in the French capital when she and 129 others were murdered by gunmen and suicide bombers aligned with ISIS. She was the only American slain in the atrocity last November.

Her father, Reynaldo Gonzalez, of El Monte, California, has now sued the trio of US companies, claiming the web giants’ websites and apps were used by the terror group’s masterminds to brainwash people into joining their ranks, profit from video ads, and coordinate attacks.

“Without defendants Twitter, Facebook and Google (YouTube), the explosive growth of ISIS over the last few years into the most-feared terrorist group in the world would not have been possible,” the lawsuit, filed in the northern district of California on Tuesday, argued [PDF].